A New Method for Identification and Minimization of Distortion Sources in GaN HEMT Devices Based on Volterra Series Analysis

摘要

This letter mainly focuses on providing theoretical justification for possible gallium–nitride (GaN) device linearity improvement, interpreting the key physical origins of third-order distortion (IMD3). Based on the bias-dependent $S$-parameter measurement data of field-plate (FP)-free $hbox{8} times hbox{125} muhbox{m}$ GaN high-electron mobility transistor (HEMT), IMD3 is modeled using classical Volterra series theory. Through this technique, device diagnosis is carried out for efficiently localizing the distortion behavior. Further, device linearity is shown to improve by appropriately tuning the gate–drain feedback capacitance by taking advantage of FP technology proving the analysis to be a powerful tool for developing GaN HEMT technology.